Move comment text to `#error' stanza.

loader/i386/linux.c

@@ -143,10 +143,8 @@ allocate_pages (grub_size_t prot_size)
   real_mode_mem = 0;
   prot_mode_mem = 0;
   
-  /* i386-pc port adds lower memory to heap, which collides with
-     `real_mode_mem' allocation below.  */
 #ifdef GRUB_MACHINE_PCBIOS
-#error
+#error i386-pc port adds lower memory to heap, which collides with `real_mode_mem' allocation below
 #endif
 
   auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t);